BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an automatic follow-up projecting system capable of tracking a moving object automatically to project a picture, an animation, characters and the like at a predetermined position thereon. The automatic follow-up projecting system according to this invention is able to automatically track the moving object and effect image projecting, so that this system can be widely used as a medium of advertizing, new or the like which is image-projected on an airship or a balloon floating in the air from the roof of such as a building.

2. Description of the Prior Art

In conventional image projecting apparatus, an image is projected at a predetermined position of a fixed object such as a screen or the like by a slide projector, a cinema projector or the like which includes a luminous source. Because the object is fixed or cannot move, it is necessary for a viewer to come to the position or the vicinity thereof for the purpose of watching a projected image. Conventionally image projecting is seldom performed with a moving screen or the like, and if it has been needed, the image projecting apparatus is manually followed up to the moving object such as screen.

Recently the commercial or advertisement is popularly made by using a balloon or an airship. However, it is a difficult operation itself to project an image onto the object under such condition that the projected object, for an instance in case of a balloon, is considerably moved changing directions frequently. In this situation, it has been a very important assignment to improve the operability of the projection apparatus. Consequently, the apparatus which is not a kind of that operated by mannual control, allowing an automatic tracking for projecting an image securely in response to the movement of a moving object, has been strongly desired.

SUMMARY OF THE INVENTION

This invention was made in consideration of the circumstances mentioned above and the object of this invention is to provide an automatic follow-up projecting system, particularly in the case where it is necessary to project an image on a moving object, which can be fully, automatically operated so as to reduce a great deal of the labour for operators, and ensure the projecting by the smooth and steady automatic tracking in response to the movement of an object.

According to one aspect of this invention, for achieving the objects described above, there is provided an automatic follow-up projecting system comprising: a turn table which can rotate arbitrarily in a horizontal direction and in a vertical direction in response to a moving object provided with a light emitting member, an image projecting apparatus which is mounted on the turn table having directivity so as to project an image at a predetermined position of the moving object, an image pick-up means having a field of view catching the above-mentioned light emitting member, and a calculating controlling means connected to the image pick-up means and the turn table in order to drive and control the turn table in a manner of processing light quantity signals obtained from said light emitting member by the image pick-up means and calculating for tracking the moving object.

According to another aspect of this invention, there is provided an automatic follow-up projecting system comprising; a turn table which can rotate arbitrarily in a horizontal direction and in a vertical direction in response to a moving object having a reflective member, an image projecting apparatus which is mounted on the turn table having directivity so as to project an image at the predetermined position of the moving object, an infrared ray irradiating means mounted on the turn table for irradiating infrared rays onto the reflective member, an infrared ray image pick-up means having a field of view catching infrared rays reflected from the reflective member, and a calculating controlling means connected to the infrared image pick-up means and the turn table in order to drive and control the turn table in a manner of processing amount of the infrared rays and calculating for tracking the moving object.

The nature, principle and utility of the invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

• FIG. 1 shows a schematic configuration according to this invention;
• FIG. 2 shows a block diagram of a control system according to this invention;
• FIG. 3 shows a relation between video signals and images;
• FIG. 4 shows a time chart illustrating an example associated with an input-output of a timing generating circuit;
• FIG. 5 shows a block diagram illustrating an example of an accumulating circuit;
• FIG. 6 shows a block diagram illustrating an area counting circuit;
• FIG. 7 shows a relation between a center position of figure on an infrared ray radiating member and a target position;
• FIG. 8 shows a flow chart illustrating an example of calculations by software; and
• FIG. 9 to FIG. 11 show respectively a schematic configuration of another embodiment according to this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments according to this invention are described hereinafter based on the attached drawings.

FIG. 1 shows a schematic configuration according to this invention and an infrared ray radiating member 2 for being tracking is attached at a predetermined position on an object 1 such as a ballooon and the like. The infrared ray radiating member 2 may be whatever irradiates infrared rays to an infrared ray image pick-up unit 12 positioned in the coaxial direction of an image projecting unit 11 (such as a slide or cinema projector, in addition, a laser beam projector, a video projector or the like). An image is projected on the object 1 by the directional image projecting unit 11 provided on an electrically-driven turn table 10, and the infrared ray image pick-up unit 12 having a field of view catching the infrared ray radiating member 2 is fixed on the image projecting unit 11 in one body. The image projecting unit 11 can project arbitrarily in horizontal and vertical directions with exact directivity by driving the electrically-driven turn table 10. Video signals VS from the infrared ray image pick-up unit 12 are image-processed by an image processing apparatus 100 which is explained hereinafter, and the processed image frame is displayed on a monitor 3 such as a CRT and the like. Drive signals DS processed by the image processing apparatus 100 drive the turn table 10 via a driving section 4 of an amplifier or the like to control the projecting position of the image projecting unit 11, so as to track the shift of the object 1, the infrared ray radiating member 2, or the target point keeping a fixed distance away from the object 1 and the infrared ray radiating member 2.

When the infrared ray radiating member 2 attached on the object 1 irradiates infrared rays to the infrared ray image pick-up unit 12 positioned in the coaxial direction of the image projecting unit 11, the infrared ray image pick-up unit 12 attached to the image projecting unit 11 catches a high luminous point as an image and the video signals VS are binarized in the image processing apparatus 100. A central value of a primary moment on a binary image is calculated on real time, for example, every 1/60 second, and signals corresponding to the movement amount are transmitted on the basis of the positional data to the electrically-driven turn table 10 of the image projecting unit 11 via the driving section 4. The electrically-driven turn table 10 is controlled by the transmitted signals so that the projecting direction of the image projecting unit 11 may be automatically changed and automatic follow-up projecting may be carried out for the moving object 1, the infrared ray radiating member 2 or the target point keeping a fixed distance away from the object 1 and the infrared ray radiating member 2.

In FIG. 2, the image processing apparatus 100 is mainly described in details, the image projecting unit 11 mounted on the electrically-driven turn table 10 is rotated in the horizontal direction by a motor 13, and in the vertical direction by a motor 14. A projecting operation to the arbitrarily directions can be carried out in combination with these rotations. An infrared ray image pick-up unit 12 of which an image pick-up part is provided with a lens system having a field of view covering a part of whole part of a directional region of the image projecting unit 11, outputs a two dimensional address information f (x, y) as video signals VS in time series. The video signals VS are inputted to a binarizing circuit 101, and converted into binary signals P (x, y) represented by "0" or "1" with a predetermined threshold level T. FIG .3 shows a relation between image information (oblique line part) and X-Y address, and illustrate that f (x, y) is a video signal VS on an address x and an address y. In the binarizing circuit 101, if f (x, y) ≧T (threshold level) then P (x, y) =1, if F(x, y)<T then P (x, y) =0.

The video signals VS are inputted to a synchronous separating circuit 102 in which they are divided into horizontal synchronous signals HD and vertical synchronous signals VD, and these divided signals HD and VD are inputted into a timing signal generating circuit 103. Clock signals CLK from a clock generating circuit 104 have been inputted into the timing signal generating circuit 103 and the clock signals CLK have been outputted at the timing in response to the horizontal resolution of an image. The timing signal generating circuit 103 outputs the clock signals CLK which are inputted into accumulating circuits 110, 112 and an area counting circuit 111, and outputs signals R indicating a measuring region of the image information and similarly outputted signals R are inputted into the accumulating circuit 110, 112 and the area counting circuit 111. Further, the timing generating circuit 103 generates horizontal address signals XAD to input them into the accumulating circuit 110, and also generates vertical address signals YAD to input them into the accumulating circuit 112, thereby generating signals YR indicating the completion of measuring to input them into calculating circuits 120 and 130. The each timing for the vertical synchronous signals, the signals R indicating the measuring region, and the signals YR indicating the completion of measuring is shown in FIG .4.

The accumulating circuit 110 calculates Σ Σ Y, the both circuits 110 and 112 are the same configuration. That is, the accumulating circuit 110 as shown in FIG.5 comprises an AND circuit 113 and an adding circuit 114 and the adding circuit 114 is activated to add the address signals XAD sequentially at the timing of the clock signals CLK only when the both binary signal P (x, y) and signals R indicating the measuring region are "1" and an enable signal ES is also "1". The adding circuit 114 is also cleared by inputting the vertical synchronous signal VD, and the added output Σ Σ X representes Σ Σ P (x, y) × x. Similarly, the output Σ Σ Y of the accumulating circuit 112 represents Σ Σ P (x, y) × y. These added values Σ X and Σ Y are inputted into the calculating circuits 120 and 130 respectively. The configuration of the area counting circuit 111 is as shown in FIG .6, a counter 116 to be cleared by the vertical synchronous signals VD, counting with the clock signals CLK the output CN from the AND circuit 115 into which the binary signals P (x, y) and the signals R indicating the measuring region are inputted, outputs are S as a counted value. The counted area S is inputted into the calculating circuits 120 and 130.

The calculating circuits 120 and 130 divide the accumulated result (a primary moment) for X axis and Y axis, respectively, by the area S (the moment of the zero degree) after the signals YR indicating the completion of the measuring are inputted. Then, the center position of the infrared ray radiating member 2 is calculated to output X (=Σ Σ X/S) and Y(=Σ Σ Y/S), thereby renewing the output values. FIG .4 shows the circumstances, wherein the S, ΣX, ΣY are initialized by the input of the vertical synchronous signals VD (at the time points t₀ and t₁) , and the S, ΣX, ΣY are measured during the time span T₀, and the measured values are renewed during the time span T₁.

Calculating circuits 121 and 131 calculate the differences ΔX and ΔY between the center position 21 of the infrared ray radiating member 2 and the target position 22 as shown in FIG.7. Generally, the center position 21 of the infrared ray radiating member 2 corresponds with the target position 22, through it is also allowed that tracking operation may be carried out keeping a fixed distance away from the infrared ray radiating member 2. The differences ΔX and ΔY calculated by the calculating circuits 121 and 131 are inputted into motor controllers 4X and 4Y respectively, and the motor controllers 4X and 4Y drive motors 13 and 14 respectively. The differences after the operation described above are fed back so that a deviation between the target position 2 and the center of an image becomes to zero. It is noted that the target position for projecting can be changed adding a setting device capable of setting a position from outside. The configuration as mentioned above is all provided with hardwares by using the calculating circuits 120, 121 and 130, 131, through a configuration with software can be also possible by using such as a microcomputor in accordance with a flow chart shown in FIG. 8.

Although the embodiment described above represents the case that an infrared ray radiating member 2 is set at the position beyond the image projecting region, an infrared ray radiating member can be set within the image projecting region and visible light can be applied to the light emitting member. When a visible light is applied to the light emitting member, a normal kind of an image pick-up means is available. Further, another configuration as shown in FIG .9 may be also available for the automatic follow-up projecting system wherein an infrared ray reflective medium 20 is mounted in place of the infrared ray radiating member 2 and an infrared ray irradiating unit 15 is provided on the electrically-driven turn table 10, so that an infrared ray image pick-up unit 12 can catch light amount of the reflected infrared rays from the infrared ray reflective medium 20. Visible light can be also applied to this embodiment. Moreover, the configurations of the blocks as shown in FIG.5 and FIG.6 are not limited by this embodiment. In case that the follow-up operation is carried out using the infrared rays, the effect is considerably appreciable, particularly at night because the light for the automatic follow-up is invisible.

In the above description, the image projecting unit 11, the infrared ray image pick-up unit 12 and an infrared ray irradiating unit 15 are attached to the electrically-driven turn table 10, therefore it is difficult to control in direction the system directly by the electrically-driven turn table 10 when these units are large sized or overweighted. To deal with this, as shown in FIG. 10 or FIG. 11 a mirror 30 such as surface-evaporated mirror or the like is adapted to be attached to the electrically-driven turn table 10 while the image projecting unit 11, the infrared ray image pick-up unit 12 and the infrared ray irradiating unit 15 may be fixed at a separated place. In this case, an incident image also reaches through the reflection of the mirror 30 to the infrared ray image pick-up unit 12, yet the control of the mirror 30 is carried out in the same way when a mirror is not applied.

It is noted that this invention can be applied to a camera capable of automatically following up a subject by using a camera for film, video or the like in place of the image projecting unit 11.

As mentioned above, the use of the automatic follow-up projecting system according to this invention requires no operator, and allows a high speed, responsive smooth tracking. Because the system can steady track a moving object to project an image thereon, it is possible that an advertising image may be projected onto an airship or a balloon, alternatively news may be announced with a character image and/or animation being projected, and many other variation of the applications can be expected according to this invention.

It should be understood that many modifications and adaptations of the invention will become apparent to those skilled in the art and it is intended to encompass such obvious modifications and changes in the scope of the claims appended hereto.